Fert Calculator Result - Dosing question - The Planted Tank Forum
LinkBack Thread Tools Display Modes
post #1 of 6 (permalink) Old 07-15-2014, 04:52 PM Thread Starter
Planted Tank Obsessed
jasa73's Avatar
PTrader: (23/100%)
Join Date: Jun 2007
Location: Cambridge, MA
Posts: 480
Fert Calculator Result - Dosing question

My plants are exhibiting signs of nutrient deficiency and I've decided to up my EI dosing. I want to ensure I'm providing surplus nutrients then slowly draw back one fert at a time, observe and fine tune.

I have injected c02 controlled via pH meter, and drop checker is colored light green to almost yellow. Lighting is 1 Finnex Ray 2. My tank is a 110 gallon. In general plants have been doing well but I'm recovering from K and N03 deficiencies. I also suspect Phosphorus and Mg. Only algae is BGA which is dying back.

So my question is the results from the calulator here.


For example I wanted to dose Mg. I put in my parameters..The results are as follows.

"To reach your target of 5 ppm Mg you will need to add 19.193 g MgSO4.7H2O to your 100.0 US gal aquarium to yield Element ppm/degree Mg 5.00 S 6.60 dGH 0.28

Dose these levels 2-4 times a week for EI. Classic EI depends on good CO2, good circulation, and regular water changes. Light past moderation is not so important. "

MY QUESTION: Does this mean I need to dose a total of 19 grams for the week...and spread that out 2-4 times....OR does that mean I dose 19 grams EACH time I dose? It seems 19g would be a lot to add 3x a week. 19g translates to about 4tsp.

Last edited by jasa73; 07-15-2014 at 05:00 PM. Reason: add
jasa73 is offline  
Sponsored Links
post #2 of 6 (permalink) Old 07-15-2014, 07:15 PM
Planted Tank Guru
Zorfox's Avatar
PTrader: (5/100%)
Join Date: Jun 2012
Location: Gainesville, FL
Posts: 2,105
That's 19 grams per dose. It does sound like a lot but remember classic EI provides excess nutrients.
Zorfox is offline  
post #3 of 6 (permalink) Old 07-15-2014, 08:01 PM Thread Starter
Planted Tank Obsessed
jasa73's Avatar
PTrader: (23/100%)
Join Date: Jun 2007
Location: Cambridge, MA
Posts: 480
Thanks for the response. That's what i had thought but needed to check.
jasa73 is offline  
post #4 of 6 (permalink) Old 07-16-2014, 12:11 AM
Planted Tank Guru
PTrader: (0/0%)
Join Date: Jan 2010
Location: Contra Costa CA
Posts: 11,721
What is the Calcium level? Plants use Ca and Mg in a ratio of about 4 parts Ca to 1 part Mg.

If you are just dosing Mg to make the GH test come out right, that is not the right way to do this.

If you have already tested the Ca, and that level is OK, but you know the Mg is way too low, then that is good to do what you are doing.
Diana is offline  
post #5 of 6 (permalink) Old 07-17-2014, 01:21 PM
Wannabe Guru
mrkookm's Avatar
PTrader: (94/100%)
Join Date: Apr 2007
Location: Delaware
Posts: 1,600
Fert Calculator Result - Dosing question

To get the 5ppm for your 100gal volume you will dose the 19+ grams ONCE. Now, unless you have liquid Ca flowing from your tap you do not need any more than 5-7ppm Mg. Sure you can dose more, but it is not needed.

Regarding the N & K deficiencies you mentioned.. if you are over 10 for each it is highly unlikely what your seeing is from lacking macros.

from my iP5 via Tapa Pro

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

The Junkie

Last edited by mrkookm; 07-17-2014 at 01:22 PM. Reason: ........
mrkookm is offline  
post #6 of 6 (permalink) Old 07-17-2014, 04:12 PM Thread Starter
Planted Tank Obsessed
jasa73's Avatar
PTrader: (23/100%)
Join Date: Jun 2007
Location: Cambridge, MA
Posts: 480
Thanks for the replies. The reason for my concern about Mg was because my java ferns were struggling. Digging around this and other forums it seemed that java ferns had a need for more magnesium and phosphate under higher lights. I checked my city water report and did a test and it appeared that there was plenty of calcium but no Mg.

With respect to N03 and K deficiencies, its hard to say what my ppm were, since i EI dose according to recommended levels and dont measure. BUT i was noticing pinholes in the java fern, anubias, and my stems were melting. I suspected a nitrate deficiency because leaves, especially on my anubias were turning yellow at the tip and slowly melting back. Also I had an outbreak of BGA.

As a result I upped my EI dosing and added MgS04. Im already noticing a huge difference. BGA has died back, any that i remove does not return. Java Fern has greened back up. Explosive growth on rotala colorata, rotala macandra ,rotala walichii and A. renkeii mini. Anubias greened up again from yellow. With respect to Magnesium I suspect that I may not need as much. I used only a 1tsp per dose as opposed to the 4tsp. So something went right here. I was thinking about slowly backing off one fert at a time and observe results but plants seem happy and I'm wondering if I'd need more ferts as plant mass expands. I'm thinking i'm going leave things as they are and keep watching.
jasa73 is offline  


Quick Reply

Register Now

In order to be able to post messages on the The Planted Tank Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome